University of Illinois Urbana-Champaign

Mid-ir Sub-doppler Eresolution Spectrometer Using An Enhanced-cavity Absorption Cell Coupled With A Wide Beam

Abe, Masashi

Content Files
TJ13_Abstract.pdf
TJ13_Abstract.txt
TJ13_Presentation.pptx

Permalink

https://hdl.handle.net/2142/50795

Description

Title
Mid-ir Sub-doppler Eresolution Spectrometer Using An Enhanced-cavity Absorption Cell Coupled With A Wide Beam
Author(s)
Abe, Masashi
Contributor(s)
  • Sasada, Hiroyuki
  • Okubo, Sho
  • Iwakuni, Kana
Issue Date
2014-06-17
Keyword(s)
Instrument/Technique Demonstration
Date of Ingest
  • 2014-09-17T16:54:56Z
  • 2015-04-14T18:37:16Z
Abstract
We have introduced a wide-beam-coupled enhanced-cavity absorption cell (ECAC) into a 3-$\mu $m difference-frequency generation spectrometer in order to reduce transit-time broadening of Lamb dips. It contains concave and convex mirrors with a curvature radius of $\pm $7 m separated by 37.5 cm, has a finesse of 770, and is coupled with a Gaussian beam having a $1/\text{e}^2$ radius of 1.9 mm at beam waist. The spectrometer is applied to record sub-Doppler resolution spectra of the $\nu _3$ band of CH$_4$ and the $\nu _1$ and $\nu _4$ bands of CH$_3$D, and the transit-time broadening is estimated 30 kHz for these molecules. The observed Lamb dips are about 80 kHz (HWHM) wide, which is one third of those recorded using another ECAC coupled with a $1/\text{e}^2$ radius of 0.7 mm at the beam waist. Some $A_1$-$A_2$ splittings of the low $J$ levels for CH$_3$D are first resolved, and the absolute transition frequencies are determined with a relative uncertainty of 10$^{-9}$.
Publisher
International Symposium on Molecular Spectroscopy
Type of Resource
text
Genre of Resource
Conference Paper / Presentation
Language
English
Permalink
http://hdl.handle.net/2142/50795
DOI
https://doi.org/10.15278/isms.2014.TJ13
Copyright and License Information
Copyright 2014 by the authors. Licensed under a Creative Commons Attribution 4.0 International License. http://creativecommons.org/licenses/by/4.0/

Owning Collections

Abstracts & Presentations - 2014 International Symposium on Molecular Spectroscopy PRIMARY